The GBA tournaments would be disappointing. The only non-allowed Pokemon (Mew, Celebi, Jirachi, Deoxys) are the ones which dont impact as much. The only way someone is going to win this is by using legendaries. Almost EVERY (smart) team will be filled with Mewtwo, Kyogre, Lugia, Ho-oh, Groudon, Blissey. I find it a bit sad that they didnt ban them for this... Using Legendaries is not a test of someone's skill.
I think the Miracle Crystal images will look good. They made alot of good images in LM and I think they'll continue this on in MC. I found alot of the Holon Phantom pictures to be a little disappointing, compared to LM.